Catalysts for the reaction of nitrile carbonates-active hydrogen compounds

ABSTRACT

A METHOD OF PREPARING ORGANIC COMPOUNDS HAVING ONE OR MORE UREA, UTETHANE OR THIOURETHANE GROUPS BY REACTING CYCLIC NITRILE CARBONATES OF THE FORMULA:   (2-(O=)-1,3,4-DIOXAZOL-5-YL)N-R   WHEREIN R IS AN ORGANIC RADICAL WHICH IS FREE OF REACTIVE HYDROGEN ATOMS AND N IS 1 OR MORE, SUCH AS, ADIPODI (NITRILE CARBONATE), WITH NUCLEOPHILIC COMPOUNDS CONTAINING A REACTIVE HYDROGEN ATOM, SUCH AS POLYESTER AND POLYETHER POLYOLS IN THE PRESENCE OF A CATALYTICALLY-EFFECTIVE AMOUNT OF AN N-OXIDE OF AN AMINE AT A TEMPERATURE OF ABOUT 50* TO 150*C.

United States Patent O 3,793,254 CATALYSTS FOR THE REACTION OF NITRILECARBONATES-ACTIVE HY- DROGEN COMPOUNDS Larry G. Wolgemuth, Cherry Hill,NJ., assignor to Atlantic Richfield Company, New York, N.Y. No Drawing.Filed Dec. 4, 1972, Ser. No. 312,088 Int. Cl. C08g 22/00 U.S. Cl.260-775 R 20 Claims ABSTRACT OF THE DISCLOSURE A method of preparingorganic compounds having one or more urea, urethane or thiourethanegroups by reacting cyclic nitrile carbonates of the formula:

wherein R is an organic radical which is free of reactive hydrogen atomsand n is 1 or more, such as, adipodi (nitrile carbonate), withnucleophilic compounds containing a reactive hydrogen atom, such aspolyester and polyether polyols, in the presence of acatalytically-effective amount of an N-oxide of an amine at atemperature of about 50 to 150 C.

BACKGROUND OF THE INVENTION The present invention relates to an improvedmethod for preparing organic compounds having one or more urea, urethaneor thiourethane groups by reacting compounds having a reactive hydrogenatom with cyclic nitrile carbonates. More particularly, the presentinvention relates to an improved method of preparing oragnic compoundshaving one or more urea, urethane or thiourethane groups by reactingcompounds having a reactive hydogen atom with cyclic nitrile carbonatesin the presence of a catalyst comprising organic amine oxides.

In the past, it has been common practice to prepare ureas, urethanes andthiourethanes by the reaction of an isocyanate and an activehydrogen-containing material. Although the use of isocyanates for thepreparation of ureas, urethanes and thiourethanes is quite popular andextensively employed, there are a number of problems with this reaction.First, the isocyanates are unstable and present storage and handlingdifiiculties. Secondly, many isocyanates, particularly the aliphaticisocyanates, are highly toxic. Thirdly, the reactivity of the -NCO groupprecludes premixing of the isocyanate with the reactivehydrogen-containing material to form a single component system withoutfirst blocking the terminal isocyanate groups. However, curing theblocked isocyanate materials to liberate the blocking group and toreactivate the --NCO group requires high curing temperatures. Finally,in the production of foamed polyurethanes, polythiourethanes andpolyureas, via the isocyanate route, it is necessary to go through theexpense and inconvenience of adding a separate foaming agent or of usingan excess of isocyanate and water to obtain the required gas release.

The disadvantages mentioned above are not, however, present in a processfor preparing such organic compounds by condensation of a compoundcontaining a reactive hydrogen with a compound having the followingstructural formula:

3,793,254 Patented Feb. 19, 1974 a: Ce

wherein R is an organic radical free of reactive hydrogen atoms and n is1 or more. For convenience, the compounds identified by the abovestructural formula will be hereafter referred to as cyclic nitrilecarbonates.

There are several techniques for carrying out the reaction of an activehydrogen-containing material with cyclic nitrile carbonates in thepresence of catalysts. For example, in U.S. Pat. 3,531,425 a process isdescribed in which the reaction is carried out in the presence of astrong base, such as tertiary amines, having a pKa above 8. In U.S. Pat.3,652,507 the reaction is carried out in the presence of solublecatalysts containing a first metal from Groups III through V of thePeriodic System and a second metal from Groups I, H or the iron seriesof Group VIII of the Periodic System. In U.S. Pat. 3,702,320, it isdisclosed that the reaction may be carried out in the presence of asoluble compound of aluminum, tin, titanium, zinc, bismuth or iron at atemperature of about 120 to 150 C., provided that when the metal isaluminum, tin titanium or bismuth no metal of Group I, II or the ironseries of Group VIII is present and when the metal is zinc or iron, thereaction is conducted in the absence of metals of Groups III through V.It was found in accordance with U.S. Pat. 3,652,507 that in most casesstrongly basic materials (alkali metal alkoxides, tertiary amines, etc.)must be utilized in conjunction with the catalyst in order to obtainreaction rates which are acceptable for foam formation. In copendingapplication Ser. No. 276,640, filed July 31, 1972 by Larry G. Wolgemuth,it is disclosed that the reaction may be carried out in the presence ofan inorganic or an organic fluoride, such as KP, CsF, RbF,tetraalkylammonium fluoride, etc.

It is, therefore, an object of the present invention to prepare organiccompounds having one or more urea, urethane or thiourethane groups byreacting a cyclic nitrile carbonate with an organic compound having anactive hydrogen in the presence of a novel catalyst. Another object ofthe present invention is to provide an improved process for thepreparation of organic compounds having one or more urea, urethane orthiourethane groups by reacting cyclic nitrile carbonates with anorganic compound having an active hydrogen in which it is unnecessary toutilize a strong basic material.

These and other objects and advantages of the present invention will beapparent from the following detailed description.

SUMMARY OF THE INVENTION A method of preparing organic compounds havingone or more urea, urethane or thiourethane groups comprising reacting atleast one cyclic nitrile carbonate of the formula:

wherein R is an organic radical free of nucleophilic groups asdetermined by the Zerewitinoff test and n is 1 or more, with anucleophilic organic compound having at least one reactive hydrogen atomas determined by the Zerewitinoif test in the presence of acatalytically effective amount of an N-oxide of organic amines. Thepreferred class of catalysts are the tertiaryamine N-oxides. Thereaction may be carried out at a temperature of about 50 C. to about 150C. It is preferred to conduct the reaction at a temperature of about C.to C.

DESCRIPTION OF THE INVENTION As previously indicated, urea, urethane andthiourethane organic compounds may be prepared by prior art techniquesby condensing nucleophilic compounds having areactive hydrogen .atomwith cyclic nitrile carbonates in the presence of a strong base as acatalyst or metallic catalysts having metal ions, such as Al+ Sn+ Sn+ TiZn, etc. However, in the latter case it was found that in most cases inorder to obtain rates of reaction acceptable for foam formation, it wasalso necessary to utilize a strongly basic material in conjunction withthe metal ion. By way of contrast, it has been found inaccordancewiththe present invention that it is not necessary-to usestrongly basic compounds in conjunction with the catalyst provided thecatalyst system contains an organic amine oxide.

A broad spectrum of organic amine oxides are useful in catalyzing thereaction; and, in general, any tertiary amine oxide which does notcontain atoms or radicals which would interfere with the catalyticactivity of the amine oxide may be usedas the catalyst in the reactionbetween the cyclic nitrile carbonates and the nucleophilic compoundscontaining a reactive hydrogen atom. As used herein, the terms tertiaryamine oxides and N-oxides of tertiary amines are used to describe theclass of organic compounds containing a primary, secondary or tertiaryamine in which an oxygen atom is attached directl to the nitrogen atom.The general formula of compounds having this structure is:

wherein R R and R are organic groups free of interfering substituents.Included in this class of compounds are tertiary alkyl, aryl, alkaryl,aralkyl, heterocyclic amine oxides, and amine oxides in which thesubstituents on the nitrogen atom are a mixture of alkyl and arylgroups. In addition, the substituents may be mixtures of two or more ofthe above groups. Amine oxides which are included in the above classesare trimethylamine oxide, tripropylamine oxide, dimethylethylamineoxide, tricyclohexylamine oxide, dimethylethylamine oxide,triphenylamine oxide, tritolylamine oxide, dimethylphenylamine oxide,ethyldiphenylamine oxide, tri-p-ethylphenylamine oxide,pyridine-N-oxide, l-benzazine-N-oxide, pyrroline-N-oxide, etc. Thepreferred class of tertiary amine oxides is the tertiary alkyl amineoxides. Representative members of this class are trimethylamine oxide,dimethylethylamine oxide, tributyl amine oxide, etc. As mentioned above,mixtures of two or more of any of the above catalysts may be includedwhere it is desired to alter the efficiency of other characteristics ofthe catalyst.

The total number of carbon atoms present in the tertiary amine oxidepreferably varies from three, in the case of trimethyl amine oxide, upto 60. It is usually most preferable, particularly in the case in whichthe tertiary amine oxide is a tertiary alkyl amine oxide, that thenumber of carbon atoms present in the tertiary amine oxide be in therange of 3 to 12.

Many of the amine oxide compounds mentioned form hydrates. While eitherthe anhydrous or the hydrated forms of the oxides may be used, it ispreferable to use and maintain the amine oxide catalysts in theiranhydrous form.

Each of the above-mentioned tertiary amine oxides maybe utilized alone.However, the amine oxide compounds may also be combined with one or moremetals from Groups III through V of the Periodic System. Preferably, acombination of one of the amine oxide compounds and a metal from GroupsIII through V are utilized.

As previously indicated, cyclic nitrile carbonates, useful in accordancewith the present invention, have the following formula:

wherein R is an organic radical having from 1 to about 200,000 carbonatoms and is free of nucleophilic groups and can be aliphatic oraromatic including cycloaliphatic, alkaryl or aralkyl radicals and n is1 to about 100,000.

The R radical in the above formula for the cyclic nitrile carbonaterepresents a monomeric or polymeric organic structure which is free ofnucleophilic groups containing reactive hydrogen atoms as determined bythe Zerewitinoff test. A compound which contains a reactive hydrogen asdetermined by the Zerewitinoif test is one which, when contacted with aGrignard solution of methyl iodine, will effect the liberation ofmethane by decom position of the Grignard reagent. Frequently R willconsist essentially of carbon and hydrogen atoms and by consistingessentially of carbon and hydrogen is meant that the essentialcomposition of the radical is carbon and hydrogen but that there can beincluded therein other elements as well, so long as they do notmaterially affect the radicals basic characteristic of beingnon-interfering in the condensation reaction of the cyclic nitrilecarbonate group with the hydroxyl group. Examples of non-interferinggroups which can be present in R and which contain elements other thancarbon and hydrogen are alkoxy, nitro, and halo groups. The R radicalcan be aromatic, e.g., of 1 to 3 aromatic rings (fused or non-fused) ornon-aromatic and, when the latter, can be cyclic or acyclic andsaturated or ethylenically or acetylenically unsaturated. Groups whichdecompose easily when slightly heated or agitated as, for example,vinylacetylenic groups, are preferably not present in R. Acyclic Rs canbe straight or branched chain. The cyclic nitrile carbonate group can beattached to an aromatic ring carbon atom, or to a cycloaliphatic ringcarbon atom, or to a non-ring carbon atom. When R is aromatic, it ispreferred that no two cyclic nitrile carbonate groups occupy orthopositrons with respect to one another. The molecular weight of theacyclic nitrile carbonate will often be below about 75,000.

The cyclic nitrile carbonate used in the process of the presentinvention can be prepared by phosgenating the corresponding hydroxamicacid, preferably while the latter is in solution in a stable solvent.The hydroxamic acid, 1n turn, can be prepared by various methods knownin the art, such as, for example, by reacting the methyl ester of thecorresponding carboxylic acid with hydroxylamine. Examples of suitablecyclic nitrile carbonates include, for instance, cyclohexane nitrilecarbonate; ethane nitrile carbonate; propane-Z-nitrile carbonate; ethenenitrile carbonate; cyclohexene-3-nitrile carbonate; benzene nitrilecarbonate; 2,2-diphenylpropane-4,4'-di(nitrile carbonate);4-vinylbenzene-1-nitrile carbonate; 1-vinylanthracene-3,9- di(nitrilecarbonate); butane-1,4-di(nitrile carbonate); hexane-1,6-di(nitrilecarbonate); benzene-1,4-di(nitrile carbonate);naphthalene-l,4-di(nitrile carbonate); etc.

The cyclic nitrile carbonate used in the process of the presentinvention can also be derived from other cyclic nitrile carbonates.Thus, for example, an addition-polymerizable, ethylenically-unsaturated,cyclic nitrile carbonate, such as ethene nitrile carbonate, can beaddition polymerized with a dissimilar monomer, such as styrene oracrylonitrile, to yield a polymeric cyclic nitrile carbonate which issuitable for use in the process of the present in vention. Also, apolyfunctional cyclic nitrile carbonate, such as hexane-1,6-di(nitrilecarbonate) can be condensedrearranged in stoichiometrically excessiveamounts with a hydroxyl group-containing compound as used in the presentprocess to yield a urethane group-containing cyclic nitrile carbonatewhich is suitable for use in the process of the present invention. Thelatter condensation-rearrangement can be caltalyzed by any suitablesystem-for example, using a strong base or combination metal catalyst ofthe prior art, or by using the catalyst of this invention. Also,suitable cyclic nitrile carbonates for use as reactants in the presentprocess can be obtained by con (lensing-rearranging stoichiometricallyexcessive amounts of a polyfunctional cyclic nitrile carbonate with acompound having one or more primary amino, secondary amino, or mercaptogroupsfor example, as disclosed in the aforementioned U.S. Pats.3,531,425 and 3,652,507, which disclosures are incorporated herein byreference. The resultant condensation-rearrangement products containurea or thiourethane groups, in addition to the unreacted, excess cyclicnitrile carbonate groups.

Although the production of the low molecular weight aliphatic andaromatic cyclic nitrile adducts wherein n ranges up to 4 has beendescribed in detail in U.S. Pats. 3,532,425 and 3,652,507, highermolecular weight adducts, wherein n is 5 or higher, can be prepared bythe homo polymerization of the vinyl derivatives of the cyclic nitrilecarbonates, for example, vinyl nitrile carbonate having the structure:

Likewise, these vinyl compounds can be copolymerized with one or morepolymerizable monomers, for example, olefinically unsaturatedhydrocarbons, esters, ethers, aldehydes, ketones, nitriles, amides,halogen compounds, carboxylic acid or anhydride compounds and likemonomers which are not nucleophilic compounds, i.e., those free ofreactive hydrogen atoms as determined by the Zerewitinolf test, or freeof positive metal ions or a positive ammonium ion which would react withthe cyclic nitrile group. Examples are the monoand diolefins such asethylene, propylene, butadiene, styrene, vinyl ethers, vinyl esters, theacrylates, methacrylates, acrylonitrile, vinyl chloride, maleicanhydride and the like. The production of these high molecularpolycyclic nitrile adducts is likewise disclosed in U.S. Pats. 3,480,595and 3,652,507 both of which are incorporated herein by reference.

The polymerization can be catalyzed by conventional polymerizationcatalysts, particularly of the free-radical type such as the peroxidetype compounds, e.g., benzoyl peroxide, the azo compounds, ultra-violetlight, and beta or gamma irradiation.

The nucleophilic organic compounds reacted with the cyclic nitrilecarbonates according to the present invention are organic compoundshaving at least one reactive hydrogen atom and include compounds havingthe reactive hydrogen present in one or more hydroxyl, primary amino,secondary amino, or mercapto groups. These nucleophilic compounds may besimple compounds of relatively low molecular weight, or they may be highmolecular weight compounds, such as polymeric materials, for instance,having molecular weights of at least about 200 up to about 75,000 ormore. The nucleophile can be mono-functional, that is, containing onereactive hydrogen, or polyfunctional (including difunctional), that is,containing more than one reactive hydrogen. The preferred nucleophiliccompounds contain a reactive hydrogen at terminal ends of the longestchain of the molecule.

In accordance with the invention, one or more of the nucleophiliccompounds may be reacted with the cyclic nitrile carbonate to provide avariety of organic products containing urethane, urea or thiourethanegroups or mixt-ures of the foregoing. The products may be monomeric orpolymeric depending upon the cyclic nitrile carbonate and nucleophileselected, the proportions of reactants employed and the reactionconditions utilized.

Suitable nucleophilic organic compounds having an active hydrogen atom,for use in the present process, include compounds having the activehydrogen present in --OH, NH, NI-I SH, SO NH SO OH, COOH, CSNH and CONHRgroups. Nucleophiles having an active hydrogen atom may be furtheridentified as those that give a positive Zerewitinofi test, that is, anycompound which, when added to a Grignard solution of methyl iodide,liberates methane by decomposition of the Grignard reagent. Nucleophiliccompounds, of the desired type, are disclosed in detail in U.S. Pats.3,531,425 and 3,652,507 which disclosures are incorporated herein byreference. Of particular interest are polyols (hydroxyl-rich compoundshaving at least 2 OH groups) as disclosed in U.S. Pat. 3,702,320 whichdisclosure is also incorporated herein by reference.

The amounts and ratio of catalysts employed will also vary dependingupon the type of product, the temperature, and the desired properties ofthe product. By Way of example, the catalyst is desirably present in anamount of from about 0.01% to about 5%, preferably from about 0.1 toabout 2% by weight, based on the weight of the reactants. The metal ionof Groups III to V of the Periodic Table, when used, may be present inan amount of about 0.1% to about 5%, preferably from about 0.1 to about2%, by weight of the reactants. Amounts above or below these ranges maysometimes be effectively used but it is preferred that the concentrationof tertiary amine oxide and metal ion be within these limits. The ratioof tertiary amine oxide catalyst to Groups III to V metal ion may be upto about 2:1 and preferably in the range of 0.3 to 1:1.

The reaction is generally carried out at a temperature between about 50C. and 150 C. and preferably between 70 C. and C.

The reaction which is catalyzed by the improved method of the presentinvention may be carried out as a single stage operation or in multiplestages employing more of the same or different cyclic nitrile carbonatereactant or the same or different H-containing nucleophilic compound.Thus, in polymer product production, the process, for example, may bewhat is termed in the art as a one shot process. Alternatively, aprepolymer of the nitrile carbonate reactant and the activehydrogen-containing reactant can be prepared by employing an excess ofeither reactant but preferably an excess of the cyclic nitrile carbonate reactant. The prepolymer formed may then be subsequently reactedwith either more of the same or a different cyclic nitrile carbonatereactantor with more of the same or a different nucleophile depending onthe groups terminating the ends of the prepolymer.

When the nucleophilic compound contains an active hydrogen in a hydroxylgroup, then monoor polyurethane products are prepared; while if thegroup containing the active hydrogen is an amino group, monoor polyureaproducts are obtained. Reaction of the cyclic nitrile adduct reactantwith both a hydroxyl group-containing compound and an aminogroup-containing compound, either simultaneously or sequentially,provides urea-urethane products. And when the nucleophilic compoundcontains an active hydrogen in a mercapto group, then monoorpolythiourethane products are obtained.

As indicated above, the improved process of the present invention hasbeen found to be capable of providing polycondensation products havingexceptionally high molecular weights, for example, having weight averagemolecular weights of about 150,000 or higher. Moreover, where thesepolycondensation products are prepared from difunctional cyclic nitrilecarbonates and difunctional nucleophilic compounds, they are soluble ina variety of organic solvents, such as chloroform, tetrahydrofuran,dimethylformamide, dimethylsulfoxide, and aromatic hydrocarbon solvents.This unique solubility characteristic of the high molecular weightpolymers is apparently a result of a substantially linear (i.e.,non-crosslinked)configuration of the polymer molecules, whichconfiguration is further evidenced by the thermoplastic character of theproducts. Especially preferred polycondensation products of the presentinvention are those having weight average molecular weights of at leastabout, say, 200,000 or even 300,000; and further unique are thoseproducts of greater than about 500,000 molecular weight. Preferably,these are obtained from difunctional reactants and are soluble in, forexample, chloroform, although it is recognized that even thedifunctional reactants-derived products of the present invention becomeless soluble as their molecular weights increase.

It is possible in accordance with the present invention to producecellular or nonporous plastics, including films, coatings, adhesivelayers, impregnated compositions, castings, moldings, and the like.However, in the production of polyurethane foams by the process of theinvention it is not necessary, as it is in conventional prior artprocesses, to employ an extraneous foaming or blowing agent since thecyclic nitrile carbonate reactants contain their own internal or builtin blowing agent namely, the carbon dioxide gas they evolve duringreaction with the nucleophilic compounds. Conventional foaming agents,however, may be employed if desired, among which may be listed-lowboiling solvents, such as benzene, toluene, acetone, ethyl ether, butylacetate, methylene dichloride, carbon tetrachloride, and the like, aswell as agents which will decompose to evolve an inert gas as, forinstance, ammonium carbonate, sodium bicarbonate, N,N'-dimethyl-N,N-dinitroso-terephthalamide, para, para'-oxybis(benzenesulfonic acid),azodicarbonamide, benzene sulfonyl hydrazide, axodiisobutyronitrile,paratertiary butyl benzoylazide and the like.

Formulation of polyurethane foams can follow the well establishedpractice of the art with the notable exception that the conditions ofthe reaction between the cyclic nitrile carbonate compound andnucleophilic compound be controlled to elfect the reaction at a rateslow enough to preclude escape of the evolved CO gas before gelation tothe extent suflicient to entrap the evolved gas and form a cellular,elastomeric polyurethane has occurred.

When preparing foamed products by the method of the present invention,it is generally preferred to employ at least a trifunctional reactant,which can be either the cyclic nitrile carbonate, the nucleophiliccompound or both. Thus, for example, excellent polyurethane foams can beprepared by condensing a difunctional cyclic nitrile carbonate with atriol to yield a cross-linked product.

If desired, surface active agents might be in concentrations of about0.1 to 5% by weight of the reactants to stabilize the foam. Generallyused are silicone emulsifiers and non-ionic surface active agents, suchas ethylene oxide condensates of vegetable oils, alcohols, and organicacids.

In accordance with the usual practice, inert, inorganic or organicfillers or both, and other additives may be included in the reactionmixture. Suitable inert, inorganic materials include, for example, clay,talc, silica, carbon black, asbestos, glass, mica, calcium carbonate,antimony oxide, and the like. Organic fillers include, for instance, thevarious polymers, copolymers and terpolymers of vinyl chloride, vinylacetate, acrylonitrile, acrylamide, styrene, ethylene, propylene,butadiene, divinylbenzene, etc. Other additives which may be addedinclude plasticizers, such as dioctyl phthalate, di(Z-ethylhexyl)adipate, etc., extenders, softeners, coloring agents and emulsifiers.

The products produced by the invention have many uses. For example, theproducts are excellent materials for use in the preparation of castings,molds, sealants, potting compounds, insecticides, adhesives, coatings,films, foams, etc.

In a preferred method of preparing, for example, polyurethanes by theprocess of the present invention, the polyol reactant is degassed priorto being admixed with either the catalyst or the poly(nitrilecarbonate). The purpose of the degassing is to remove water andmolecular oxygen from the system. Water might serve to react with anddilute the effect of some of the catalysts which can be used in thepresent process; also, it can react with the cyclic nitrile carbonatereactant under certain conditions. Certain hydroxyl group-containingcompounds, e.g., poly(tetramethylene ether), are sensitive to molecularoxygen at the present reaction temperatures. Thus, the reason forpreferring, under appropriate circumstances, to purge moisture andoxygen from the hydroxyl group-containing reactant. The degassing canoften be accomplished by subjecting the polyol to a temperature of aboutto 150 C. at about 0.25 to 50 mm. Hg pressure for from 15 to 60 minutes.After the addition of the catalyst, further degassingsay, for up toabout 4 hoursunder the same conditions may be conducted. After additionof catalyst and such further degassing, a substantially oxygen-freeatmosphere, for example, a nitrogen or other inert gas atmosphere, isadvantageously created and maintained in the reaction vessel, duringwhich time the desired poly(nitrile carbonate) is added, preferably insmall portions over periods of, say, about three minutes to two hours.During the addition of the carbonate, the reaction mixture can bestirred. Following complete addition of the carbonate, the temperatureof the reaction mixture is maintained at a level and the reaction timeis selected so as to produce the desired product. The reaction mixtureis advantageously stirred during the reaction. It is often advantageousto add a solvent for the urethane product, such as xylene, to thereaction mixture gradually, as the mixture thickens, to keep the mixtureat a stirable viscosity. This is especially so where the product is athermoplastic polyurethane. The amount of solvent added will preferablynot exceed the total weight of the reactants. Preferred solvents forthis purpose are aromatic solvents and cyclic ether solvents which areliquid at room temperature having boiling points of at least about 60C., and contain no ester or nitro groups. Examples of such include, inaddition to the xylenes, amylbenzene, bromobenzene, chlorobenzene,substituted toluenes, such as buty1-, chloro-, bromotoluenes, dioxaneand tetrahydrofuran, etc.

The following working examples of the present invention illustratespecific embodiments. Unless otherwise indicated, parts and percentagesare on a weight basis.

Example I To a 100 ml. tumbler was added 30.0 g. of a 3000 M polyethertriol (Hydroxyl No.=56.4) and 0.20 g. of trimethylamine-N-oxide. Thismixture was heated to 100 C. with gentle stirring until thetrimethylamine-N-oxide dissolved. To the mixture was added a siliconesurfactant (0.30 g.) and stannous octoate (0.30 g.) and the mixturestirred; then 3.96 g. of ADNC, adipodi(nitrile carbonate), was added andthe mixture stirred for 20 seconds at 1000 r.p.m.s. The mixture was thenrapidly transferred to a 1000 ml. polypropylene beaker which was heatedto 100 C. by an oil bath. The reaction mixture began to foam. Thereaction mixture did not gell but collapsed to an oil.

Example 11 The procedure of Example I was repeated except that 0.30 g.of trimethylamine-N-oxide was used as the sole catalyst. The reactionimmediately foamed out of the tumbler upon the addition of ADNC.

Example III The procedure of Example III was repeated except that a 3000M polyester triol (Hydroxyl No.=56.2) was used in place of the polyethertriol. The reaction produced a polyurethane foam.

9 Example V The procedure of Example IV was repeated except that 0.50 g.of 4-methoxypyridine-N-oxide was substituted for mg 0.25 g. oftrimethylamine-N-oxide. The reaction produced a tacky polyurethane foam.

"Although the invention has been described with partidillal reference tospecific examples, it is contemplated that modifications of these may beemployed and, accordingly, the breadth of the invention is to be limitedsolely byithe scope of the appended claims.

I claim:

In the method of preparing an organic compound having one or more urea,urethane or thiourethane groups obtained by condensing (A) anucleophilic organic compound having at least one reactivehydrogen-containing radical selected from the group consisting ofprimary amino radicals, secondary amino radicals, hydroxyl radicals andmercapto radicals with (B) a cyclic nitrile carbonate having thestructure:

wherein R is an organic radical free of nucleophilic groups and havingfrom 1 to about 200,000 carbon atoms and n is 1 to about 100,000

the improvement which comprises carrying out the condensation reactionby contacting said (A) and (B) with a catalytically elfective amount ofa tertiary amine oxide.

'2. The improvement of claim 1 wherein the substituents ong the tertiaryamine oxide are selected from the group consisting of alkyl, aryl,alkaryl, aralkyl, cyclic, alycyclic, he terocyclic radicals and mixturesof these.

3. The improvement of claim 2 wherein said tertiary amine oxide contains3 to 60 carbon atoms.

4;. The improvement of claim 3 wherein said tertiary amine oxide is atertiary alkyl amine oxide containing 3 to 12 carbon atoms.

5. The improvement of claim 3 wherein said tertiary amine oxide is atertiary aryl amine oxide containing 10 to 3 alkyl substituents attacheddirectly to the aromatic nuclei.

6. The improvement of claim 3 wherein the substituents on the amineoxide are a mixture of alkyl and aryl groups.

7. The improvement of claim 1 wherein the condensation reaction iscarried out in the presence of a tertiary amine oxide and at least onemetal from Groups III to V of the Periodic System.

8. The improvement of claim 1 wherein R is a hydrocarbon radical.

9. The improvement of claim 1 wherein R is an aliphatic radical having 2to 30 carbon atoms.

10. The improvement of claim 9 wherein the cyclic nitrile carbonate isadipodi(nitrile carbonate).

11. The improvement of claim 1 wherein n is 2 to 4.

12. The improvement of claim 11 wherein n is 2.

13. The improvement of claim 1 wherein the nucleophilic organic compoundis a polyol.

14. The improvement of claim 13 wherein the polyol is a polyester triol.

15. The improvement of claim 13 wherein the polyol is a polyether triol.

16. The improvement of claim 2 wherein said tertiary amine oxide isanhydrous.

17. The improvement of claim 7 wherein the ratio of tertiary amine oxideto said metal ion is up to about 2:1.

18. The improvement of claim 7 wherein the ratio of tertiary amine oxideto said metal is about 0.3 to 1:1.

19. The improvement of claim 3 wherein said tertiary amine oxide ispresent in an amount of about 0.01 to 5% based on the total weight ofreactants.

20. The improvement of claim 4 wherein said amine oxide is present in anamount of about 0.1 to 2% based on the total weight of reactants.

References Cited UNITED STATES PATENTS 3,480,595 11/1969 Burk et al.26077.5 R 3,531,425 9/1970 Burk et a1. 26037 N 3,652,507 3/1972 Burk etal. 260-859 R 3,702,320 11/1972 Fritok et a1. 260-859 R MAURICE J.WELSH, Primary Examiner

